According to Marc Levy of the Associated Press, 245,000 of the commonwealth’s 8.3 million voters (3%) changed parties this year.
About half moved to the Republican party and a third switched to become Democrats. This would suggest Pennsylvanians are more motivated, for whatever reason, to vote in the GOP Presidential primary.
At the same time, Democrats attracted more third party and unaffiliated voters than the Republicans (52,200 to 42,600). The Dems have also signed up 70,000 new voters while the GOP got 55,500.
Overall, Democrats have just over 4 million registered voters in Pennsylvania while Republicans have 3.1 million.